In the art there are many different types of conveyor belts, and the present invention is especially directed to the type of conveyor belts built up from a large number of substantially identical belt modules, typically manufactured from plastic in an injection moulding process.
The belt modules are typically connected in a hinge-like manner such that the conveyor belt may bend around sprocket wheels in either end of the conveyor which sprocket wheels conveys the propulsion power to the conveyor belt. Furthermore, the hinge connection between adjacent belt modules may be such that the belt modules may flex sideways relative to each other in order to allow the conveyor belt to travel through curves etc.
These types of conveyor belts are typically arranged on a substructure, typically made from steel or stainless steel where the path of the plastic conveyor belt is delimited by rails or flanges. The conveyor belt may also be provided with means extending below the conveyor surface which means interact with guard rails in the substructure in order to determine the path of the conveyor belt. Particularly for applications where the substructure is made for a fixed width of the conveyor belt, it is necessary to replace the conveyor when it is worn our or when other characteristics of the conveyor belt are desired by a conveyor belt of the exact same width in order to provide a stable and reliable travel of the conveyor belt.
The life expectancy of injection moulded plastic conveyor belts may be upwards of 8-10 years and as such the original manufacturer of the conveyor belt may have gone out of business or may have changed dimensions of the modules such that it is not possible to replace the modules making up the entire conveyor belt with a similar module having the possibility of providing the same width, and as such the substructure needs to be replaced as well. Typically, the life expectancy of a substructure made from stainless steel is substantially longer than 10 years in that the tear and wear on this structure relative to the plastic injected belt modules is considerably more durable.
In the art is known to mount wear parts on side faces of the modular belt links, see for example U.S. Pat. No. 5,280,833 in order to prolong the effective service life of the conveyor belt. These wear parts however are not suitable nor foreseen to adapt the modular conveyor belt to the sub-structure. On the contrary the sub-structure must be dimensioned to allow for the extra space required by these wear parts. The wear parts are typically made from wear resistant materials, such as Kevlar or carbon reinforced polymers.